Modern farmers strive to improve the management of increasing amounts of farm acres. Improving management requires farmers to be able to quickly prepare the soil for each season""s farming operations. This haste has driven the need for more efficient and larger farming equipment.
Implements such as harrows, packers, or combined harrow-packers were some of the earliest implements to be made with widths exceeding sixty feet in the field operating position. As tractor horsepower has increased over time, larger tillage implements have been made available. These larger implements require a mechanism for compactly folding the implement for practical and safe transport over the highway. U.S. Pat. No. 4,821,809, patented by Summach et al., discloses a convenient mechanism for such folding.
The conventional method of folding tillage implements is by folding wing sections along forward aligned axes such that the wings are folded to a generally upright position. Double folding wing sections may have outer sections that fold inwardly and downwardly from the ends of inner wing sections in five section winged implements. In the case of these conventional wing implements, the minimum implement width that can be achieved by such folding is limited by the width of the center section. As a result, road transport may still be somewhat restricted as these implements often exceed twenty feet or more in transport width.
Road transport standards in North America are beginning to follow the standards set in Europe in which maximum road transport widths and heights for agricultural implements are being defined. Large implements that have conventional folding wing sections are not able to be folded such that they fall within width and height limits that may be generally 3 meters wide and 4 meters high. Some U.S. states have adopted transport width limits of 13.5 ft.
Forward or rear folding implements provide some relief with respect to such transport limits. However, implements must also be made to function with the accurate seeding ability that conventionally folded implements have become capable of. Although some rear or forward folding multibar tillage implements have been developed, they do not demonstrate the accurate depth control required for farming operations.
One problem is that a tillage-packer combination for drill seeding requires the gang supporting tillage elements to be maintained parallel to the ground through a range of adjustable operating levels. The drawbar disclosed in Summach ""809 raises or lowers the first attached gang of elements in a rotatable manner through its field and transport ranges of motion. A level manner of height adjustment is required for tillage elements.
Another problem that must be overcome for compact folding is the avoidance of the packer elements of the second gang striking the tillage elements of the first gang when raised to the transport position. If compact folding is not required, then the downward rotation of the suspended second gang may be limited so as not to impact the elements of the first gang. But when compact folding is desired, the elements of the second gang are in direct alignment with the ground elements of the first gang so that alignment is achieved.
Therefore, a multibar implement is required for the tillage of high acre farms with both speed and efficiency.
It is an object of the invention to provide a compactly folding tillage implement that includes a spring mechanism interconnecting the rockshaft and the first tool frame to exert spring force on the first tool frame for urging the first tool frame toward the field.
It is a feature of the invention that the spring mechanism includes a spring surrounding an adjustment rod supported on a support arm extending rearwardly from said rockshaft.
It is another feature of the invention that the rockshaft has a rearwardly extending arm terminating in an abutment member that is engagable with the first tool frame when pivoted into a transport position.
It is an advantage of the invention that the pivotal movement of the rockshaft into the transport position relaxes the spring weight transfer mechanism. It is another object of the invention to provide a compact folding implement capable of being configured either as a multibar implement or as a single bar implement for row crop applications, thereby providing economy in manufacturing.
It is still another object of this invention to provide a compact folding implement capable of accurate seeding across its working width even while traversing uneven slopes.
An implement having a toolbar or frame to which a first tool gang is attached may also have a second tool gang attached to the rearward end of the first tool gang so both sets of gangs are drawn by the implement frame or toolbar for field operation. Such an implement avails itself for compact folding in which the first tool gang may be rotated to a general upright position and the second tool gang becomes suspended from the now upper end of the first gang. Such an implement is patented in U.S. Pat. No. 4,821,809 to Summach et al. According to the patent, the implement frame or toolbar may be folded for compact folded transport. This design works particularly well for harrow-packer combined implements.
One key advantage of this style of folding is that for a harrow-packer combined implement, the packers are pulled inward toward the implement frame substantially before they are lifted from the ground, which significantly reduces the torsion required of the toolbar or frame elements in order to produce sufficient lifting force to effect compact folding.
This invention provides an offset for the alignment of the second gang elements from the first gang ground elements so they do not impact when the implement is folded.
A spiral guide is provided on the pivotal connection on which the second implement gang is attached to the first implement gang. When the implement is folded to transport position, the spiral guide shifts the second gang out of alignment with the first gang so their elements do not impact.
These and other objects, features, and advantages are accomplished according to the present invention by providing a forwardly folding tillage implement that carries a number of ground engaging tools on a tool gang frame disposed to the rear of a carrier frame. A rockshaft is disposed between the carrier frame and the tool gang frame and is movable between four rotated positions about two axes of rotation. A control mechanism controls the relative angular position of the rockshaft. A support mechanism is disposed rearwardly of the axes of rotation to support the rear of the tool gang frame above the ground in the field working position. An abutment member restrains the relative rotation between the rockshaft and the tool gang frame to fully support the tool gang frame on the rockshaft upon rotation of the rockshaft. A spring mechanism is provided which interconnects the rockshaft and the first tool frame to exert a spring force on the tillage tools supported on the first tool frame to urge the tools into the ground. The spring mechanism is supported on a support arm extending rearwardly from the rockshaft.